ShaderMask class

A widget that applies a mask generated by a Shader to its child.

For example, ShaderMask can be used to gradually fade out the edge of a child by using a new ui.Gradient.linear mask.

Sample code

This example makes the text look like it is on fire:

new ShaderMask(
  shaderCallback: (Rect bounds) {
    return new RadialGradient(
      center: Alignment.topLeft,
      radius: 1.0,
      colors: <Color>[Colors.yellow, Colors.deepOrange.shade900],
      tileMode: TileMode.mirror,
    ).createShader(bounds);
  },
  child: const Text('I’m burning the memories'),
)

See also:

  • Opacity, which can apply a uniform alpha effect to its child.
  • CustomPaint, which lets you draw directly on the canvas.
  • DecoratedBox, for another approach at decorating child widgets.
  • BackdropFilter, which applies an image filter to the background.
Inheritance

Constructors

ShaderMask({Key key, @required ShaderCallback shaderCallback, BlendMode blendMode: BlendMode.modulate, Widget child })
Creates a widget that applies a mask generated by a Shader to its child. [...]
const

Properties

blendMode BlendMode
The BlendMode to use when applying the shader to the child. [...]
final
shaderCallback ShaderCallback
Called to create the dart:ui.Shader that generates the mask. [...]
final
child Widget
The widget below this widget in the tree. [...]
final, inherited
hashCode int
The hash code for this object. [...]
read-only, inherited
key Key
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

createRenderObject(BuildContext context) RenderShaderMask
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget. [...]
updateRenderObject(BuildContext context, RenderShaderMask renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject. [...]
createElement() SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
inherited
didUnmountRenderObject(RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
@protected, inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
toDiagnosticsNode({String name, DiagnosticsTreeStyle style }) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by toStringDeep. [...]
inherited
toString({DiagnosticLevel minLevel: DiagnosticLevel.debug }) String
Returns a string representation of this object.
inherited
toStringDeep({String prefixLineOne: '', String prefixOtherLines, DiagnosticLevel minLevel: DiagnosticLevel.debug }) String
Returns a string representation of this node and its descendants. [...]
inherited
toStringShallow({String joiner: ', ', DiagnosticLevel minLevel: DiagnosticLevel.debug }) String
Returns a one-line detailed description of the object. [...]
inherited
toStringShort() String
A short, textual description of this widget.
inherited

Operators

operator ==(dynamic other) bool
The equality operator. [...]
inherited